A pet food dish prevents ants and other crawling insects from gaining access to the food in it. The improved dish uses a combination of two or more water obstacles, or moats, and one or more climbing obstacles, or deflectors, to achieve its purpose. The dish generally consists of two sections: an upper section that contains one or more bowls into which food or water may be placed; and a lower moat or tray section that contains insect-deterring obstacles and traps.
Moated pet food bowls have been described in the prior patent art by:
DuMond et al who teach, in U.S. Pat. No. 3,441,003, a two piece bowl having a base section with a moat surrounding a central stanchion. An upper, food-containing section has a centrally located pedestal-like projection on its bottom surface. Dumond et al's moat section is intended to be filled with an insecticide, following which the food-containing section is mated to the moat section by inserting the pedestal-like projection into the stanchion.
Ahuna, in U.S. Pat. No. D314,454, shows a pet dish having an upper food-containing section. A moat-like region appears to be provided in a lower portion of Ahuna's bowl.
Studies by the inventors have shown that a single water-filled moat, such as those shown by Ahuna and by DuMond et al, is ineffective in keeping ants and other crawling insects from reaching food in a pet dish. When faced with a moated dish similar to the ones shown by Ahuna or by DuMond et al, ants have been observed to crawl up the outer wall of the base, swim across the moat, crawl up the pedestal, across the bottom surface of the top portion of the composite structure, down the inner surface of the sloping outer wall of the upper section of the bowl and up the outer surface of that wall to reach the food in the dish. Thus, it appears that prior art moated pet dishes are ineffective against crawling insects unless, as is taught by DuMond et al, the moat is filled with an insecticide (preferably one that acts quickly enough to kill insects before they can swim across the moat and climb into and contaminate the pet food in the dish).